As reported previously in Linux magazine online news and by Brian Proffitt, all Windows 8 systems will ship with Secure Boot enabled. To recap, this UEFI specification associates the firmware with a signing key that prohibits users from installing a new operating system. The majority of Linux desktop systems are installed over an OEM version of Windows, so the potential for problems is significant.

This week, however, the Linux Foundation and its Technical Advisory Board announced their plan to enable Linux (and other open source distributions) to continue operating under Secure Boot enabled systems. In the announcement, James Bottomley wrote, “In a nutshell, the Linux Foundation will obtain a Microsoft Key and sign a small pre-bootloader which will, in turn, chain load (without any form of signature check) a predesignated boot loader which will, in turn, boot Linux (or any other operating system).”

According to the announcement, the pre-bootloader will employ a “present user” test to ensure that it cannot be used as a vector for any type of UEFI malware to target secure systems. “The pre-bootloader can be used either to boot a CD/DVD installer or LiveCD distribution or even boot an installed operating system in secure mode for any distribution that chooses to use it. The process of obtaining a Microsoft signature will take a while, but once it is complete, the pre-bootloader will be placed on the Linux Foundation website for anyone to download and make use of,” Bottomley said.

Bottomley noted that this pre-bootloader “provides no security enhancements over booting linux with UEFI secure boot turned off,” and the Linux Foundation welcomes efforts by various distros to tackle the problem and improve platform security. Thus, the pre-bootloader can be seen as a stop-gap measure giving distributions time to come up with plans that take advantage of UEFI secure boot.

You can read the announcement at linuxfoundation.org. The source code for the Linux Foundation pre-bootloader is available as Loader.c.